Abstract
During the fast development of nanotechnology in the past decade, most of the research efforts have been focused on the preparation of nanometer-sized functional electronic devices. Joining multiple phases within a given one-dimensional nano-structure in its radial or axial direction results in the formation of two distinctive heterostructures, namely, coaxial nanocables or heterojunctions. Zhang et al. first reported a laser ablation process for the synthesis of SiC-SiO2-BN/C nanocables and amorphous B-SiO2-C nanocables. Shi et al. prepared a three-layer nanocable possessing a crystalline Si core, an amorphous SiO2 intermediate layer, and an amorphous C outer sheath using a combined laser ablation and thermal evaporation technique. A standard route to prepare nanoscale heterojunctions is to produce the desired vapors and organize their flow during the nanostructure growth. Hu et al.reported the synthesis of the heterojunctions made of multi-walled carbon nanotubes (CNTs) and Si nanowires and on a reproducible rectifying behavior of this metal-semiconductor junction.